Isotope Shifts in Beryllium-, Boron-, Carbon-, and Nitrogen-like Ions from Relativistic Configuration Interaction Calculations

Energy levels, normal and specific mass shift parameters as well as electronic densities at the nucleus are reported for numerous states along the beryllium, boron, carbon, and nitrogen isoelectronic sequences. Combined with nuclear data, these electronic parameters can be used to determine values of level and transition isotope shifts. The calculation of the electronic parameters is done using first-order perturbation theory with relativistic configuration interaction wave functions that account for valence, core-valence and core-core correlation effects as zero-order functions. Results are compared with experimental and other theoretical values, when available.Comment: 56 pages, 1 figure, Atomic Data and Nuclear Data Tables (2014

INFLUENCE OF SOCIO-ECONOMIC FACTORS ON FARMERS’ USE OF MOBILE PHONES FOR AGRICULTURAL INFORMATION IN NIGERIA

Farmers use mobile phones to access information needed to improve their agricultural practice. However, in cases where they do maximize their mobile phone utilization, they may be hindered by some socio-economic factors which may lead to inadequate access to agricultural information. Therefore, this study investigated the influence of socio-economic factors on famers’ use of mobile phones for agricultural information in Nigeria. The research adopted a survey design. The study population was 9,650 registered farmers in Yewa South Local Government, Ogun State, Nigeria. The proportionate stratified random sampling technique was used. The instrument used was structured questionnaire. Data were collected from 363 farmers; thus the study had 93%. Data was analyzed using descriptive statistics, Regression and Multi regression analysis. Findings from this study revealed that majority of the farmers use mobile phones daily (75.5%). It was further showed that farmers use mobile phones for specific purposes such as making phone calls (mean= 3.47), and receiving text messages (mean= 2.90). The findings also revealed that farmers use mobile phones to acquire different types of Agricultural information such as fertilizer and pesticide information (mean=2.52), and market information (mean=2.31). High tariff deductions from telecommunication companies (mean=3.53) was a major constrain. Findings further revealed that family size (β= .173; P˂.05), and Farm Size (β= .168; P˂.05) had positive significant influence on farmers’ use of mobile phones for agricultural information while Age range (β= -.031; P˂.05), Gender (β= -.027; P˂.05), Marital status (β= -.18; P˂.05), Educational qualification (β= -.031; P˂.05), Years of farming (β= -.126; P˂.05), Farm income per month (β= -.021; P˂.05) had negative influence respectively. Finally, socio-economic factors jointly influenced farmers’ use of mobile phones for agricultural information (F = 3.81; R² = .58, p \u3c .05). The study concluded that, socio-economic factors collectively contribute to farmers’ use of mobile phones for agricultural information. Therefore, it is recommended that telecommunication companies in Nigeria, in conjunction with the Federal Government, should provide a low tariff plans for farmers. This would enable them to adequately utilize their mobile phones for agricultural information

Cascade emission in electron beam ion trap plasma of W25+^{25+} ion

Spectra of the W$^{25+}$ ion are studied using the collisional-radiative model (CRM) with an ensuing cascade emission. It is determined that the cascade emission boosts intensities only of a few lines in the $10 - 3$ nm range. The cascade emission is responsible for the disappearance of structure of lines at about 6 nm in the electron beam ion trap plasma. Emission band at 4.5 to 5.3 nm is also affected by the cascade emission. The strongest lines in the CRM spectrum correspond to $4d^{9} 4f^{4} \rightarrow 4f^{3}$ transitions, while $4f^{2} 5d \rightarrow 4f^{3}$ transitions arise after the cascade emission is taken into account.Comment: 16 pages including 4 figures and 3 table

A comparative laboratory trial evaluating the immediate efficacy of fluralaner, afoxolaner, sarolaner and imidacloprid + permethrin against adult Rhipicephalus sanguineus (sensu lato) ticks attached to dogs

Variational methods are used for targeting specific correlation effects by tailoring the configuration space. Independent sets of correlation orbitals, embedded in partitioned correlation functions (PCFs), are produced from multiconfiguration Hartree-Fock (MCHF) and DiracHartree-Fock (MCDHF) calculations. These non-orthogonal functions span configuration state function (CSF) spaces that are coupled to each other by solving the associated generalized eigenvalue problem. The Hamiltonian and overlap matrix elements are evaluated using the biorthonormal orbital transformations and efficient counter-transformations of the configuration interaction eigenvectors [1]. This method was successfully applied for describing the total energy of the ground state of beryllium [2]. Using this approach, we demonstrated the fast energy convergence in comparison with the conventional SD-MCHF method optimizing a single set of orthonormal one-electron orbitals for the complete configuration space. In the present work, we investigate the Partitioned Correlation Function Interaction (PCFI) approach for the two lowest states of neutral lithium, i.e. 1s 2 2s 2 S and 1s 2 2p 2 P o . For both states, we evaluate the total energy, as well as the expectation values of the specific mass shift operator, the hyperfine structure parameters and the transition probabilities using different models for tailoring the configuration space. We quantify the “constraint effect” due to the use of fixed PCF eigenvector compositions and illustrate the possibility of a progressive deconstraint, up to the non-orthogonal configuration interaction limit case. The PCFI estimation of the position of the quartet system relative to the ground state of B I will also be presented. The PCFI method leads to an impressive improvement in the convergence pattern of all the spectroscopic properties. As such, Li I, Be I and B I constitute perfect benchmarks for the PCFI method. For larger systems, it becomes hopeless to saturate a single common set of orthonormal orbitals and the PCFI method is a promising approach for getting high quality correlated wave functions. The present study constitutes a major step in the current developments of both atsp2K and grasp2K packages that adopt the biorthonormal treatment for estimating energies, isotope shifts, hyperfine structures and transition probabilities